Many devices used for communication or entertainment purposes possess the ability to play back or reproduce sound based on a signal representing that sound. For example, a personal computer, laptop computer, or tablet computer may be used to play a video that has both image and sound. A smart-phone may be able to play such a video and may also be used for voice communications, i.e., by sending and receiving signals that represent a human voice.
In all such systems, there is a need to electrically encode the sound signal for transmission or storage and conversely to electrically decode the encoded signal upon receipt. Early forms of sound encoding included encoding sound as bumps in plastic or wax (e.g., early gramophones and record players), while later forms of analog encoding became more symbolic, recording sound as magnetic magnitudes on discrete regions of a magnetic tape. Digital recording, coming later still, converted the sound signal to a series of numbers and provided for more efficient usage of transmission and storage facilities.
However, as the transmission of sound data became more prevalent and the computing power of the devices involved became increasingly greater, more complex and efficient systems for encoding were devised. For example, many cell-phone conversations today are encoded for transmission by way of a class of LPC algorithms. Algorithms in this class such as algebraic codebook linear predictive algorithms decompose speech, for example, into a model and an excitation for that model, mimicking the manner in which the human vocal tract (akin to the model) is excited by vibration of the vocal chords (akin to the excitation). The LPC coefficients describe the model.
While algorithms of this class are efficient with respect to bandwidth consumption, the process required to create the transmitted data is quite complex and computationally expensive. Moreover, the continued increase in consumer demands upon their computing devices raises a need for yet a further increase in computational efficiency. The present disclosure is directed to a system and method that may provide enhanced computational efficiency in audio coding and decoding. However, it should be appreciated that any particular benefit is not a limitation on the scope of the disclosed principles or of the attached claims, except to the extent expressly recited in the claims. Additionally, the discussion of technology in this Background section is merely reflective of inventor observations or considerations and is not an indication that the discussed technology represents actual prior art.